Method for killing fungi with trichloro hydroxy phthalane



United States Patent 3,219,524 METHOD FOR KILLING FUN GI WITH TRICHLGRO HYDROXY PHTHALANE Hans Feichtinger, Dinslaken, Germany, assignor to Ruhrchemie Aktiengesellschaft, Obcrhausen-Holten, Germany, a corporation of Germany N 0 Drawing. Original application Oct. 29, 1962, Ser. No. 233,900. Divided and this application Oct. 8, 1964, Ser. No. 406,209 Claims priority, application Germany, Nov. 4, 1961, R 31,404 2 Claims. (Cl. 167-33) This is a division of application Serial No. 233,900, filed October 29, 1962.

This invention relates to and has as its object the production of 4,5,6-trichloro-7-hydroxyphthalane.

The production of 4,5,6,7 tetrachloro-4,7-endoxo- 4,7,8,9-tetrahydrophthalane by Diels-Alder addition of 2,5-dihydro-furane to tetrachlorofurane is known (United States Patent 2,882,199) and proceeds as follows:

01 01 0 C C C 610 C ClC i J 01( 0 H 0 01C) 0 O \l/ Cl H/ Cl Because of the small steric requirement, the Diels- Alder addition results in the production of both an endoand and exo-compound. Therefore, the product of the synthesis is a mixture of compounds of the following structural formulae:

melting point melting point 103-104 C. 105-106 C.

If the addition product is to be further processed, the mixture of stereoisomeric Compounds I and II of 4,5,6,7- tetrachloro-4,7-endoxo-4,7,8,9-tetrahydro-phthalane must be separted by a complicated chromotographic process or else the mixture of Compounds I and II has to be used per se as starting material. In the latter instance, it is obvious that a well defined uniform reaction with a well defined reaction product cannot be effected. For instance, if the endoxo mixture is subjected to further chlorination, a multiple number of compounds are obtained.

In accordance with the invention, it has now been found that a mixture of the endo-and the exo-form of 4,5,6,7 tetrachloro 4,7 endoxo 4,7,8,9 tetrahydrophthalane can be converted into a well defined uniform compound, and namely into 4,5,6-trichloro-7-hydroxyphthalane, by heating the mixture of the stereoisomeric forms I and II of 4,5,6,7-tetrachloro-4,7-endoxo-4,7,8,9- tetrahydrophthalane with 30 to 39% hydrochloric acid at an elevated temperature and an elevated pressure and thereafter recovering the 4,5,6 trichloro 7 hydroxyphthalane from the reaction mixture formed.

The conversion is advantageously effected using the hydrochloric acid in amount of 5 to 50 fold and preferably of 7 to 20 fold by weight of the initial phthalane.

ice

The reaction is expediently carried out by heating the mixture of the endo-and the exo-form of 4,5,6,7-tetrachloro 4,7 endoxo 4,7,8,9 tetrahydrophthalane and hydrochloric acid for several hours, for instance 1 to 12 hours, preferably 4 to 10 hours, at temperatures of from to 180 C. and preferably of from to C. in a closed system.

The process according to the invention is carried out at pressures amounting to from 5 to 50 atmospheres.

Heating the mixture of the endo-and exo-forms of 4,5,6,7 tetrachloro 4,7 endoxo 4,7,8,9 tetrahydrophthalane with hydrochloric acid according to the invention results in the hydrolytic cleavage of the oxygen bridge and aromatization of the system, whereby 4,5,6-trichloro- 7-hydroxy-phthalane is formed as the sole conversion product. The 4,5,6 trichloro 7 hydroxy phthalane formed has a melting point of 227.5 to 228 C. The yield obtained corresponds approximately to the theoretically calculated amount.

It is to be considered highly surprising and entirely unexpected that the simple treatment of the mixture of 4,5,6,7 tetrachloro 4,7 endoxo 4,7,8,9 tetrahydrophthalane according to the invention results in a high yield of a uniform product as here obtained.

The process of the invention allows the direct conversion of the mixture of endoand exo-forms of 4,5,6,7- tetrachloro 4,7 endoxo 4,7,8,9 tetrahydrophthalanes with the elimination of the uneconomical processing by chromatographic separation which involves much loss, into a uniform project.

The conversion reaction proceeds according to the following equation wherein the stereoisomeric formulae of the two compounds I and II of the starting material are represented by a single formula which is obtained by projecting formulae I and H into the paper plane.

, O O O or or I The reaction product is recovered from the reaction mixture in the conventional manner as, for example, by separating the liquid from the solids present in the reaction mixture and recrystallizing the residue for obtaining 4,5,6-trichloro-7-hydroxy-phthalane.

The 4,5,6 trichloro 7 hydroxy phthalane in accordance with the invention is distinguished by an exceptionally high fungicidal activity and is extremely valuable for combatting undesirable fungi. The 4,5,6-trichloro-7- hydroxy-phthalane may be used alone or in any desired conventional admixture as a fungicide.

The following example is given by way of illustration and not limitation.

EXAMPLE 27.6 g. (0.10 mol) 4,5,6,7 tetrachloro 4,7 endoxo- 4,7,8,9-tetrahydrophthalane comprising a mixture of the endoand exo-forms I and II and 200' ml. concentrated hydrochloric acid were heatedto 130 C. in an autoclave. Following a reaction time of 8 hours, the liquid was separated from the solids present in the reaction mixture by suction and the latter washed with water until free of acid. The dried residue amounting to 23.9 g. had amelting point of 215217 C. A single recrystallization from ethyl acetate resulted in the formation of 4,5,6 trichloro- 7-hydroxy-phthalane having a melting point of 227.5- 228 C. The raw yield was quantitative.

On reaction with phenylisocyanate, a phenylurethane having a melting point of 179 to 180.5 C. was obtained.

The uniform compound obtained in accordance with the invention shows fungicidal activity. The uniform compound is especially suited for use in inhibiting or fully suppressing the growth of various fungi.

The activity of the hydroxy-phthalane in accordance with the invention was determined by means of the so called plate test utilizing in the test, fungi grown on a beer wort-agar-agar nutrient. As comparison, the effect on fungi growth of zinc-ethylenebis-dithiocarbamate fungicide was simultaneously determined. The hydroxy phthalane in accordance with the invention and zincethylene-bis-dithiocarbamate were both used in dilutions of 1:1,000 and 1:10,000. The results of the tests are shown in the following tables. In the tables 25, 50, 75, and 100% inhibition of the matted growth of the respective fungi on the nutrient are given as a function of the time of exposure and the dosage of the active substance. If the substance to be tested suppresses the growth of the respective fungi beyond the area of the nutrient covered by the paper-plate impregnated with the solution of the fungicidal active compound, the effect is expressed by an estimated value, i.e. 100%.

ASPERGILLUS NIGER Percent inhibition of the matted growth after 2, 3 and 6 days at dilution ratio of Fungieidally active compound 4,5,G-trichloroJ-hydroxyphthalane 100 100 100 25 0 Zinc-ethylene-bis-dithiocarbamate 25 25 0 0 0 0 ASPERGILLUS oRYoAE Percent inhibition of the matted growth after 2, 3 and 6 days at dilution ratio of- Fungicidally active compound 4,5,6-trichloro-7-hydroxyphthalane 100 100 100 50 25 0 Zinc-ethylene-bisdithiocarbamate 100 0 0 0 O 0 PENICILLIUM ROQUEFO RTII Percent inhibition of the matted growth after 2, 3 and 6 days at dilution ratio of Fungicidally active compound 4,5,6-trichloro-7-hydroxyhthalane Zinc-ethylene-bisdithiocarbamate ALTERNARIA TENUIS Percent inhibition of the matted growth after 2, 3 and 6 days at dilution ratio of- Fungicidally active com pound 4,5,6-trichloro-7-hydroxy- FUSARIUM DIANTHI Percent inhibition of the matted growth after 2, 3 and 6 days at dilution ratio of Fungicidally active The 4,5,6 trichloro 7 hydroxyphthalane in accord ance with the invention may be used for combatting other noxious fungi, especially phytopathogenic fungi. As mentioned above, it is used in the conventional manner for fungicides, namely together with liquid or solid diluents well known in the art. Thus, for example, it may be formed into a fungicidal spray by dissolving or dispersing the same in the conventional liquid carrier materials for fungicides, eventually with addition of commercially available emulsifiers, dispersants, detergents or adhesives, further it may be formed into an aerosol in the conventional manner or into a dusting powder by admixture with a commercially available inert solid carrier material.

I claim:

1. A method which comprises applying to fungi a fungicidal amount of a component having the structural formula 2. A method which comprises applying to fungi a fungicidal composition of matter comprising a carrier with a compound having the structural formula as the active ingredient, the active ingredient being present in an amount sufficient to provide the desired fungicidal activity.

References Cited by the Examiner UNITED STATES PATENTS 2,861,919 11/1958 Gilbert 167- 33 2,875,124 2/1959 Gaertner et al 167-33 2,879,275 3/1959 Feichtinger et al. 260346.2 3,000,907 9/1961 Feichtinger et al. a- 260346.2

JULIAN S. LEVITT, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,219,524 November 23, 1965 Hans Feichtinger It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 32, for "and", second occurrence, read an line 51, for "chromotographic" read chromatographic column 4, second table, first column, line 3 thereof, for

"disdithiocar-" read bisdithiocarline 43, for "component" read compound Signed and sealed this 20th day of September 1966.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A METHOD WHICH COMPRISES APPLYING TO FUNGI A FUNGICIDAL AMOUNT OF A COMPONENT HAVING THE STRUCTURAL FORMULA 